A CAD coupled laser beam test system for digital circuit failure analysis

An automated contactless testing system that consists of a laser scanning microscope (LSM) coupled with a CAD layout database is described. Logic state detection and automated failure analysis in CMOS circuits can be done without the need of vacuum, and with a minimum of circuit environment preparation. The coupling of the LSM and the CAD layout database leads to automated node location, and minimizes the failure search because it enables the user to backtrace signal interconnections inside the circuit during the local test session.<
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